Currently, in order to increase a screen occupation ratio of a mobile terminal (i.e., a percentage of a display screen area of the mobile terminal occupied in an area of the front surface of the mobile terminal), it has been proposed in most mobile terminals to adopt a narrow frame design or even a frameless design for display screens.
In a conventional handset technology of generating sound, such as by vibrations of a handset, it is required to leave a corresponding position for the handset on the display screen, which may affect the screen occupation ratio of the mobile terminal. Therefore, this technology is gradually replaced by a piezoelectric screen technology, such as a piezoelectric actuator technology, where it does not need to occupy the display area of the display screen.
In the piezoelectric display screen technology, a voltage signal is transformed into a mechanical energy through a piezoelectric ceramic, and a component (such as a display screen or a middle frame) attached to the piezoelectric ceramic is brought to oscillate to generate a sound, thereby transmitting the sound to an ear.